Multi Layer Steel head gaskets (MLS)

[chrisallen01]

I thought I would pass on some useful information regarding MLS multilayer head gaskets having just wasted time and money by fitting one then having to remove it due to coolant leakage on my rebuilt 4.2 engine.

With the aim to try to make the engine as reliable and long lasting as possible by using the best available technologies, I'd heard that the gasket integrity when using a combination of an Iron block mated to an Aluminium head could be improved by using a MLS layered gasket to ensure a long lasting seal. MLS gaskets are also available in different thicknesses to raise the compression ratio or to restore the original cylinder head capacity following head and or block skimming. But, the surfaces of the block and head must be specially machined to reduce the roughness to a low figure (less than 50 Ra) when using a MLS type gasket otherwise the gasket will leak as happened to me. By the time I found out about this surface finish requirement the engine was back in the car so I just reverted to using an ordinary fibre composite gasket with no leakage.

[Hugo]

I had exactly the same thing happen with a Rover K series in my Rover 200 Vi. I wanted to use to highest quality gasket as these engines are prone to head gaskets, so fitted an MLS. Had the head planed too. Damn thing started leaking oil out of the front of the block. I fitted a bog-standard gasket & it's been fine ever since.